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<Title>Boost Graph Library: incident</Title>
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<H1><A NAME="sec:incident"></A>
<TT>incident</TT>
</H1>

<P>
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<TR><TH ALIGN="LEFT"><B>Complexity:</B></TH>
<TD ALIGN="LEFT"><i>O(1)</i>
</TD>
</TR>

<TR><TH ALIGN="LEFT"><B>Where Defined:</B></TH>
<TD ALIGN="LEFT">
<a href="../../../boost/graph/graph_utility.hpp"><TT>boost/graph/graph_utility.hpp</TT></a>
</TD>

</TABLE>
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<P>
<PRE>
  template &lt;class Graph&gt;
  std::pair&lt;typename graph_traits&lt;Graph&gt;::vertex_descriptor,
            typename graph_traits&lt;Graph&gt;::vertex_descriptor&gt;
  incident(typename graph_traits&lt;Graph&gt;::edge_descriptor e, Graph& g)
</pre>

This function takes an edge descriptor and returns the pair of
vertices that are <i>incident</i> to the edge. For directed graphs,
the <tt>first</tt> vertex is the source and the <tt>second</tt> vertex
is the target. This function is equivalent to the expression
<tt>std::make_pair(source(e, g), target(e, g))</tt>.


<h3>Example</h3>

<pre>
  edge_descriptor e;
  vertex_descriptor u, v;
  ...
  boost::tie(u, v) = incident(e, g);
</pre>


<br>
<HR>
<TABLE>
<TR valign=top>
<TD nowrap>Copyright &copy; 2000-2001</TD><TD>
<A HREF="http://www.boost.org/people/jeremy_siek.htm">Jeremy Siek</A>,
Indiana University (<A
HREF="mailto:jsiek@osl.iu.edu">jsiek@osl.iu.edu</A>)<br>
<A HREF="http://www.boost.org/people/liequan_lee.htm">Lie-Quan Lee</A>, Indiana University (<A HREF="mailto:llee@cs.indiana.edu">llee@cs.indiana.edu</A>)<br>
<A HREF="https://homes.cs.washington.edu/~al75">Andrew Lumsdaine</A>,
Indiana University (<A
HREF="mailto:lums@osl.iu.edu">lums@osl.iu.edu</A>)
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